User's Manual

Spectra Precision Focus 4 Total Station User Guide 31
Setting up the Instrument 2
Centering with a plumb bob
1. Set up the instrument on the tripod. See page 29.
2. Hang the plumb line on the hook of the tripod mounting screw.
3. Adjust the length of the plumb line so that the tip of the plumb bob is at the
height of the station point.
4. Loosen the tripod mounting screw slightly.
5. Using both hands to support the outer side of the tribrach, carefully slide the
instrument about on the tripod head until the tip of the plumb bob is positioned
over the exact center of the station point.
Note – To confirm that the instrument is precisely aligned, check its position from two
directions at right-angles to each other.
Leveling the instrument
When you level the instrument, use the electronic level to you make the vertical axis of
the instrument exactly vertical. During leveling, always set the instrument in the Face 1
direction. See Figure 3.1, page 38.
To level the instrument:
1. Move the bubble into the circle on the
circular level and then turn on the power.
2. Rotate the alidade until the bottom edge of
the keyboard panel is parallel to the two of
the leveling screws (B and C).
3. Use leveling screws B and C to move the
bubble into the center of the electronic
level.
4. Rotate the alidade approximately 90°.
5. Use leveling screw A to move the bubble
into the center of the electronic level.
6. Repeat Step 1 through Step 5 to center the
bubble in both positions.
7. Rotate the alidade 180°.
8. If the bubble in the electronic level
remains centered, the instrument is level.
If the bubble moves off center, adjust the
electronic level. For detailed instructions,
see Adjusting the electronic level,
page 118.
B C
A
1
A
B
C
Bottom edge
of the keyboard
panel
CB
A
2
Bottom edge
of the keyboard
panel